Congenital orbito-palpebral cyst in a case of Fraser syndrome.

A seven-year-old girl was referred to our clinic with absent eyelids and a mass which was gradually increasing in size from the right orbit. The child was diagnosed to have Fraser syndrome (cryptophthalmos, abnormal genitalia, mental deficiency, renal agenesis and abnormal ears). On examination, there was cryptophthalmos and a cystic swelling arising from the right orbit. The cyst was removed. On gross examination, there was a posterior eyeball with normal optic nerve. Placed in the anterior part of the eyeball was a cyst measuring about 2 cm in diameter filled with a yellow-coloured fluid. The cavity of the eyeball was communicating with the cyst. The cyst wall was lined by a single layer of epithelium. The posterior eyeball had well developed sclera, choroid, retina and optic nerve. There have been many reports of cryptophthalmos in Fraser syndrome. The most common eye deformity described with cryptophthalmos is microphthalmia or anophthalmia. To the author's knowledge, there is one other report of cystic eyeball with cryptophthalmos in the literature. The cyst seems to be due to a surface ectodermal anomaly, rather than a neuro-ectodermal anomaly where there is failure of invagination of the primary optic cup during development. The cyst wall in those cases has inverted retinal elements. In our case, differentiation of retinal elements was present in the posterior eyeball. The abnormality seemed to lie in the derivatives of surface ectoderm, namely the eyelids and the anterior segment structures.